Method for the production of surface representations



Patented Oct. 26, 1954 METHOD FOR THE PRODUCTION OF SURFACE REPREsENTATIoNS Conrad Reinemer, Munich, Germany No Drawing. Application February 20, 1951, Serial No. 211,986

1 Claim.

This invention relates to a method for the production of surface representations, by means of manual or mechanical, more particularly printin processes, on wood or ligniform or ligneous material.

It is an object of the present invention to provide an improved method of producing on such material any kind, of surface representations such as, for instance, portraits, sceneries, imitations of precious woods or inlaid work, imitation of precious wood in connection with pictorial representations and the like, while avoiding blending or other changes of the colors applied.

With this and further objects in view, according to the present invention before application of the surface representations substantially colorless solutions or dispersions, partly containing protein, of such an affinity and dissolving capacity in regard to the ligneous substance are applied directly on the surface which advantageously has been preliminarily treated by grinding, that the miscelles or capillaries of the wood or ligneous substance are given a filling combining chemically with the components of the Wood and filling substances, if any.

More particularly, according to my invention the ligneous surface to be provided with the surface representations is preliminarily treated in such a way that the miscelles or capillaries of the wood are filled up to such an extent that on subsequent application of painters color or printing ink the same while penetrating into the wood cannot spread therein. It is particularly advantageous to treat the wood or ligneous surface with a tannic acid in an aqueous solution. Tannin powder dissolved in water which as much as possible should be free from lime, in a proportion of 1 part by weight of tannin in parts by weight of water, proved to be suitable for such treatment.

The effect in regard to the preparation of the wood can be enhanced if the tannic acid is used in the form of pyrogallol. Therefore, the tannin powder is advantageously dissolved in hot water (about 60 C.).

I prefer to use a kind of wood containing much tannin, whereby a particularly good affinity to the tannic acid serving for the preparation process is ensured. Where a type of wood containing much tannin is used it is even possible to cause opening of the image carrier surface without the addition of tannic acid, merely by applying hot water.

When preparing the solution for the treatment,

2 care should be taken that the water does not contain lime, since even very small quantities of lime will change the tannic acid, especially the tannin, whereby the structure of the wood is also automatically changed and moreover the wood will change its color. On the other hand, it is also possible to obtain a desirable change of the color of the wood in the course of the preparation of the surface and structure, by dosing the amount of lime accordingly.

The opening up of the wood can be accelerated by preliminarily treating the surface of the image carrier with hot water before applying the solution containing tannic acid. The solution or dispersion should always be applied on the image carrier surface in a satiate form.

On cooling down of the preliminarily treated image carrier surface a protein solution, preferably of albumin, is applied. Where white of egg is used, this should be whipped intensively beforehand and intimately stirred with cold water. There may be used 1 part by weight of albumin with 2 to 3 parts by weight of water. It is advisable to add to the protein solution some raw milk, in order to avoid the formation of bubbles, if this is also applied in a satiate form. The proportion may be 1 part by weight of raw milk to 30 to 40 parts of albumin. It is also possible, for instance, to use grams of technical albumin with 1000 grams of boiled or rain water. On intensive stirring and filtering, in order to remove all impurities, this mixture may once more be diluted with water in a proportion of 1:1.

The satiate coating is allowed to stand for a couple of hours, in order that the protein may thoroughly combine with the tannin of the wood. Where a kind of wood containing much tannin is used, the first coating need not necessarily con-'- tain tannic acid; it may be sufficient to treat the surface of the wood with hot water in order to prepare the tannin contained in the wood for a ready absorption of the protein.

On drying up of the protein coating the image carrier is advantageously pressed or carefully rubbed off with cloth, or ground. Now the desired image is applied on the surface of the image carrier thus prepared, i. e. manually by conventional painting methods or by manual application or by printing, using conventional painting or printing colours. Where mechanical printing methods are used, care should be taken that the ligneous plate is of uniform thickness throughout its extension. If desired, the same shade of color can be printed by the same print- OFFICE", 1

. and/or potash chromate is suitable. manganate of. potassium forms-a chemical com pound with. tannin and precipitates the tan-nicing roller several times in superposition. This applies also with multi-color printing. The color thereby penetrates particularly intensively into the miscelles and capillaries of the wood, whereby the particular and beautiful eiTect of the image on wood is enhanced.

After the application of the image, parts.

sibly present in the wood and being dissolved by the heat treatment, whereby the wood is colored dark with simultaneous intensive relieving of the grain of the wood.

The parts of the surface treated with alkal-is are advantageously subsequently treated with diluted aqueous vinegar and finally the surface should be reground.

It is important for my novelprocess that it is possible. in pictorial representations to'use thenatural shading of the wood as part of the pic'- torial representation. Thus, highly artistic effects can be obtained. The natural color of Wood is the ideal shading for the representation of main parts in portraits. For the rest-oi the pictorial representation india inks, tempera and water colors, printing inks, mordantsand the like. can be used, i. e, individually or' in combination, in. short, all colors or agentswhi'ch' are suitable for pictorial representation.- As a mordant, preferably permanganate of potassium The peracid. Potash chromate hasv the effect of caus ing anzintensification of the colored areas treated therewith. By the: precipitation of: the tannin the: shading of the wood is. accentuated and the coloringis made light-resistant. Thusa deep, intensive brown wooden tint is obtained whichdoes not change in the course ofv the decades.

Anaddition of ferri-salt, protoxide of ir'onand-v the. like in. very small. quantities Y is advisable where certain color effectsv in the wood itself, for instance, as part of the pictorial representation, are intended. Ferri salt, protoxide of iron and the like solutions can also be used *as independent. agents for producing the: pictorial representation.

Primarily'for' obtaining light effects, correc tions and/or artistic effects parts of the surface representation may be scraped or otherwise-removed with a depth of: penetration corresponding to the desired eiiect, and preferably regroundr The-finished pictorial or graphic representa the varnish) and by rubbing (preferably with:

the eminence of the hands). For varnisln the known picture varnishes suchasspirit varnishes,v

cellulose varnishes, pyroxyline lacquer etc: may.

be used On drying up of: the varnish coatings: a .ground.

polish. consisting for instance of a shellac some tion is applied. Advantageously some oil is admixed to the ground polish and after hardening of the polish layer the image surface is rubbed OE and traces of oil are removed. For this operation a solvent for oil, for instance, benzene may be used. The finished picture can also be retouched or finish-treated for making necessary corrections or for accentuating contours, by means 'of permanganate of potassium, since this agent penetrates through the varnish into the wood. Itwill be understood that the process according to the invention is also particularly suitable for surface representations intended to form a true copy' of the grain and colors of precious woods on ordinary. wood, for instance ply-wood of fir. For this purpose, advantageously bright sorts of wood, such as, maple tree, Christs thorn- (Paliurus) or holly (Ilea: aquifolzum), birch tree, fir or linden wood. are used as image carri'ers in orderthat the transparency' ofthe bright wood may become effective through the: image of the wood grain. The surface of the: image carrier should be elected orprep'ared in such a way that it is free from constituents othertthan wood, more particularly spatula. o'r' smoother mass, since thewooden. surface-- itself becomes to a large extent part of theimageirepresenta tion. On the other hand, wood of an inferior quality" with glued-on covering: surfaces}: of veneer wood,- ii desired, which isfreextfrom knots" but may also be oi plain quality, may 'be used; Moreover, wood fibre board. hard boarder other: boards made of various fibrous substancesm ay. be used as carriersfor'wo'od. veneers; These amorphous boards: have the: advantageof being. cheap and avoiding the formation OfJst-rains; more p'articularly,- wherethese carriers are veneered. on1 both sides, preferably with: veneers; of the same thickness, in: an. opposite: directioni of the fibres. Moreover;.. the. finishetreated image carriers may form: parts of other. objectssuch as boxes; containers, doors; frames etcz, thewoo'den parts 'preparedtaccordance with the: present. invention. being; inlaid :or applied: :on'. wood or the like not treated-or" treated =with conventional staining. methods;

According to a further feature of the inven tion. the colors. to be applied: can be applied-cor; printedatfirst in' known manner. orr-a trans fer' foil avoiding a covering layer normally'nsed with transfer f'oils,. whereupon the colors are transferred by means of the transfer foil directlyon to the: wood. surface or surface containing: wood after preliminary treatment thereof. with the solution and drying,- using pressura and -if desired, heat; then the=transfer f'o'il is-dra-wn offor removed in another mannenand the carrier of the carrier, with an outer cover consistingiof' wood-,for: instance veneer, or material containing WO'OCL.

According to a still further f-eature-of thei'n venti'on the process canl-be' carried out irr such a" manner; more: particularly; series production that the component layers forming thevi'rnage carrier are introduced into 'a press which is suit able, for instance, for the production of veneer" or ply-wood; together with: the transitiv -foil; carrying the printing inks, and exposing them simultaneously to a pressure and if desired, heat.

Finally it is also possible to provide both sides of the image carrier with a color coating by applying printing inks directly or by means of transfer foils with equal or different pictorial or graphic representations, on both sides of a carrier body sandwiched on both sides with wood veneer or other Wood-containing material.

This operation permits primarily the mass production of surface representations on wood or objects containing wood, of any desired size and nature of the representation. The technique of the decalcomania picture or metachromotype or transfer picture is known, permitting the application, with little work and in rapid succession, of polychromatic representations on a plateshaped carrier of any desired thickness. Apart from the printing of the wood or wood-contain ing carrier in conventional printing processes, i. e. in successive single printing operations as mentioned above, it is also possible by this method to apply polychromatic prints on a carrier in a single operation. It is important, however, that the conventional covering layer of transfer pictures must be omitted, in order that the printing colors are connected directly with the wood when applying the transfer foil.

It is also contemplated to apply the colors in single printing operations according to the number of colors to be applied or to apply the colors in a single operation by means of a transfer foil, without affecting the effects obtainable as mentioned above.

By the additional measures as regards the carrier the production is cheapened and improved.

It has been found by experience that ply-wood boards tend to warping. Boards Warped already before the printing are unsuitable, however, for the proofing machines. By using a carrier core of cheap wood which is lined with veneer wood or the like on both sides, the chance of warping is already substantially reduced. This danger is completely excluded where the core is made in accordance with the present invention of an amorphous substance, for instance, compressed mixed materials such as very finely disintegrated wood waste, asbestos fibres or the like, and sandwiched between wooden foils of a bright color (veneer wood). Such boards of any desired thickness, veneered on both sides and provided on both sides with representations such as imitations of precious wood, may be used directly.

for instance, in the joiners trade or in furniture factories, as furniture doors and the like. The picture carrier thus obtained being practically free from distortions because in accordance with the invention the color and the varnish are applied on both sides, no new components causing different conditions of strain will be added by the further treatment.

The modern adhesives such as, for instance, the adhesive foils produced on the basis of polyvinyl acetate, ofier the possibility of introducing also the adhesives into the press in the form of foils, like the various layers of the carrier and the transfer foils, in a dry process without applying liquid adhesives. The boards made in accordance with the present invention can either be used in their original sizes or they may be cut, sewn, or punched by conventional methods to obtain smaller pieces of the desired contours.

While the invention has been described in detail With respect to a now preferred example and embodiment of the invention it will be understood by those skilled in the art after understanding the invention that various changes and modifications may be made without departing from the spirit and scope of the invention and it is intended, therefore, to cover all such changes and modifications in the appended claim.

What is claimed is:

The method of producing surface representation on wood and similar ligneous material, which comprises the pretreating of the surface of said ligneous material with hot water in order to open the pores thereof; thereafter treating the opened-up material with a colourless albumin solution, having an afiinity to the ligneous material and forming, when filling the capillaries of the same, a. chemical combination with said ligneous material; and applying colouring material in the desired shape at the desired spots on the surface of the so treated ligneous material, in order to produce the desired representations.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 216,589 Wellhouse et a1. June 17, 1879 FOREIGN PATENTS Number Country Date 272,041 Switzerland July 2, 1951 172,610 Austria Sept. 25, 1952 

